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P. Kolari

Bio: P. Kolari is an academic researcher from Lappeenranta University of Technology. The author has contributed to research in topics: Volume of fluid method & Conservation of mass. The author has an hindex of 5, co-authored 6 publications receiving 218 citations.

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TL;DR: STSM can evaluate tissue stiffness quantitatively and yield reproducible data, and was used to test elastomer samples with known mechanical properties.
Abstract: Simple but objective measurement of soft tissue consistency would be advantageous in the assessment of many neurological, lymphostatic and venous disorders. The aim of the present study was to evaluate the feasibility of using a novel hand-held computerized soft tissue stiffness meter (STSM). The STSM describes the soft tissue stiffness (STS) in the form of the instantaneous force (N) by which the tissue resists the constant deformation produced by a cylindrical intender. Firstly, the STSM was used to test elastomer samples with known mechanical properties. In the in vivo assessment, 12 healthy, nondisabled adults (age range, 24-57 years) and 16 subjects with chronic myofascial neck pain syndrome (age range, 27-55 years) were studied. To study the reproducibility (coefficient of variation (CV(%))) of the method, the measurement sites were either marked with a marker pen (marked points) or localized anatomically (unmarked points). Measurements were made from the dorsal forearm (Arm), trapezius (Tra), levator scapulae (Lev), infraspinatus (Inf) and deltoideus (Del) muscle areas. STS in the forearm was studied during different types of short-term relative isometric loading of the muscle as well as during venous occlusion. STS values of the myofascial trigger points in the Lev muscles were evaluated bilaterally. A linear, positive relationship was found between the indenter force (N) and the dynamic compressive modulus (MPa) of elastomer stiffness (r(2) = 0.90, n = 9). Intra- and interrater CVs of marked and unmarked sites varied between 4.31% and 12.06%. STS increased linearly along the relative muscle load (r(2) = 0.96) and nonlinearly during the venous occlusion (r(2) = 0.97). Statistically significant regional variation of STS was found between the different measurement sites (p < 0.05). In conclusion, STSM can evaluate tissue stiffness quantitatively and yield reproducible data.

84 citations

Journal ArticleDOI
TL;DR: The assessment of hemodynamics shows that under the flow regimes of hypotension and hypertension, the risk of atherosclerosis localization in human aorta may increase, and the focus is on variation of wall shear stress.
Abstract: A three-dimensional computer model of human aortic arch with three branches is reproduced to study the pulsatile blood flow with Finite Element Method. In specific, the focus is on variation of wall shear stress, which plays an important role in the localization and development of atherosclerotic plaques. Pulsatile pressure pulse is used as boundary condition to avoid flow entry development, and the aorta walls are considered rigid. The aorta model along with boundary conditions is altered to study the effect of hypotension and hypertension. The results illustrated low and fluctuating shear stress at outer and inner wall of aortic arch, proximal wall of branches, and entry region. Despite the simplification of aorta model, rigid walls and other assumptions results displayed that hypertension causes lowered local wall shear stresses. It is the sign of an increased risk of atherosclerosis. The assessment of hemodynamics shows that under the flow regimes of hypotension and hypertension, the risk of atherosclerosis localization in human aorta may increase.

80 citations

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TL;DR: In this article, a more simplified model based on volume of fluid (VOF) approach is suggested to simulate movements of RBCs in capillaries and also to predict RBC deformation.

42 citations

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TL;DR: In this article, a computational model of blood flow through branching geometries has been used to investigate the influence of bifurcation on blood flow distribution, and the flow analysis applies the time-dependent, three-dimensional, incompressible Navier-Stokes equations for Newtonian fluids.

23 citations

Journal ArticleDOI
TL;DR: The results obtained using the two devices during arm cooling showed a systematic disagreement in the continuously recorded MAP, and, although statistically significant, this difference cannot be considered clinically meaningful.
Abstract: Two different methods were studied for non-invasive beat-to-beat finger mean arterial pressure (MAP) measurement in 14 healthy volunteers during local arm cooling to 17°C. Fingertip skin blood flow was recorded by a laser Doppler instrument. The difference between the oscillometric beat-to-beat blood pressure measurement device (UT9201) and volume clamp monitor (Finapres) before cooling was −1.5±1.1 mmHg, and, although statistically significant, (p<0.01), this difference cannot be considered clinically meaningful. The results obtained using the two devices during arm cooling showed a systematic disagreement in the continuously recorded MAP. After a 30s period of cooling, the group-averaged difference of UT9201 minus Finapres, calculated as change from the baseline, reached (mean±SD) 8.8±6.3 mmHg (statistically significant, p<0.01).

16 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, Least Square and Galerkin methods are used to solve the problem of laminar nanofluid flow in a semi-porous channel in the presence of transverse magnetic field.

254 citations

Journal ArticleDOI
TL;DR: Until reliable diagnostic criteria have been established, there is a need for greater transparency in research papers on how a case of MTrP pain syndrome is defined, and claims for effective interventions in treating the condition should be viewed with caution.
Abstract: Objectives The aim of the literature review was to investigate the criteria adopted by "experts" to diagnose myofascial trigger point (MTrP) pain syndrome. Experts were defined as being either researchers investigating MTrP pain syndrome or the "authority" the researchers cited as a source of reference for MTrP pain syndrome diagnosis. Methods We searched electronic databases to identify relevant empirical research (excluding studies not in English and those relating to dental pathology). Of 607 possibly relevant publications 93 met our inclusion criteria. We recorded (1) the individual criterion and criteria combinations used to diagnose MTrP pain syndrome; (2) the cited "authoritative" publications and (3) the criteria recommended by the authoritative publications as being essential for MTrP pain syndrome diagnosis. Results The review identified 19 different diagnostic criteria. The 4 most commonly applied criteria were: "tender spot in a taut band" of skeletal muscle, "patient pain recognition," "predicted pain referral pattern," and "local twitch response." There was no consistent pattern to the choice of specific diagnostic criteria or their combinations. However, one pair of criteria "tender point in a taut band" and "predicted or recognized pain referral" were used by over half the studies. The great majority of studies cited publications by Travell and more recently Simons as a principal authoritative source for MTrP pain syndrome diagnosis, yet most of these studies failed to apply the diagnostic criteria as described by these authorities. Discussion We conclude that there is as yet limited consensus on case definition in respect of MTrP pain syndrome. Further research is needed to test the reliability and validity of diagnostic criteria. Until reliable diagnostic criteria have been established, there is a need for greater transparency in research papers on how a case of MTrP pain syndrome is defined, and claims for effective interventions in treating the condition should be viewed with caution.

242 citations

Journal ArticleDOI
TL;DR: Recent developments in the biology of fascia, and in particular, its associated hyaluronan (HA)-rich matrix that address the issue of MPS are summarized.
Abstract: Myofascial pain syndrome (MPS) is described as the muscle, sensory, motor, and autonomic nervous system symptoms caused by stimulation of myofascial trigger points (MTP). The participation of fascia in this syndrome has often been neglected. Several manual and physical approaches have been proposed to improve myofascial function after traumatic injuries, but the processes that induce pathological modifications of myofascial tissue after trauma remain unclear. Alterations in collagen fiber composition, in fibroblasts or in extracellular matrix composition have been postulated. We summarize here recent developments in the biology of fascia, and in particular, its associated hyaluronan (HA)-rich matrix that address the issue of MPS.

160 citations

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TL;DR: The efficacy of the current diagnostic methods of acute compartment syndrome (ACS) after leg fractures is reviewed to confirm the diagnosis in suspected patients and may have a role in the diagnosis of this condition in unconscious patients or those unable to cooperate.
Abstract: Objectives To review the efficacy of the current diagnostic methods of acute compartment syndrome (ACS) after leg fractures. Data sources A Medline (PubMed) search of the English literature extending from 1950 to May 2007 was performed using "compartment syndromes" as the main key word. Also a manual search of orthopaedic texts was performed. Study selection and extraction The results were limited to articles involving human subjects. Of 2605 primary titles, 489 abstracts limited to compartment syndromes in the leg and 577 articles related to the diagnosis of compartment syndromes were identified and their abstracts reviewed. Further articles were identified by reviewing the references. Sixty-six articles were found to be relevant to diagnostic techniques for compartment syndrome in the leg and formed the basis of this review. Conclusions Early diagnosis of an ACS is important. Despite its drawbacks, clinical assessment is still the diagnostic cornerstone of ACS. Intracompartmental pressure measurement can confirm the diagnosis in suspected patients and may have a role in the diagnosis of this condition in unconscious patients or those unable to cooperate. Whitesides suggests that the perfusion of the compartment depends on the difference between the diastolic blood pressure and the intracompartmental pressure. They recommend fasciotomy when this pressure difference, known as the Delta p, is less than 30 mm Hg. Access to a precise, reliable, and noninvasive method for early diagnosis of ACS would be a landmark achievement in orthopaedic and emergency medicine.

142 citations